The invention is for use in connection with vehicles of the type that have an expandable room. An example of such a vehicle with an expandable room is shown in Hanser U.S. Pat. No. 6,067,756. Recreational and similar vehicles have been known and used for years for traveling, camping and other purposes and also have been used as multiple purpose vehicles that permit individuals to be transported and to live for short periods of time in the vehicles. Because these vehicles are driven over public highways, there are limitations on the widths of the vehicles, and such limitations restrict the amount of interior room that is available for occupancy or storage when the vehicle is parked off the road. To overcome these limitations and to provide more useable living space when the vehicle is parked, there have been designed expandable rooms that can be extended while the vehicle is parked and retracted while the vehicle is moving over the road. Such expandable rooms greatly improve the utility of the vehicles for not only recreational purposes, but also for use in transporting small groups, such as entertainers, who spend a considerable amount of time on the road and move from location to location frequently. Some of these vehicles are quite luxurious, so in addition to the maximization of available space, aesthetics are very important.
Since the expandable rooms are quite massive, the mechanism for expanding them and then retracting them requires a considerable amount of power. Typically, expansion and retraction is accomplished using hydraulic power since most of these vehicles have hydraulic systems available for other purposes. Most known systems therefore use hydraulic cylinders to expand and retract the room, but known systems are designed in such a way that the cylinders and the associated components occupy valuable space and therefore take away from otherwise useable space. HWH Corporation has pioneered a number of extension systems that are economical regarding the use of vehicle space. One such system is a vertical cam system wherein arms that extend upwardly from a floor surface are pivotally mounted to the floor and pivotally mounted to one another. In such an arrangement, a hydraulic cylinder is used to change the relative positions of the arms and to force the extendible room to move inwardly or outwardly from a vehicle. Such a vertical cam system may be conveniently located within the arm of a sofa, or within other accessories built into the expandable room. In this manner, the extension functionality may be provided without sacrificing space that is otherwise needed for storage, occupancy, or comfort.
With such a system, or with various other room extension systems, there has been a difference in the height of the vehicle floor and the extendible room floor. Such a step-up may be undesirable for some vehicle occupants. There is therefore a need for improved mechanisms for accomplishing the expansion and retraction of expandable rooms in an efficient manner with a minimum of space required for the hydraulic mechanisms and with a flat-floor extended room position. There is also a need for providing such mechanisms that can be hidden from view by moveable housings and thus greatly improve the overall appearance of these vehicles to make them more appealing to users.
The mechanism of the invention for extending and retracting expandable rooms in vehicles employs a tension cable and cammed vertical arms wherein a first arm is pivotally anchored to a vehicle and pivotally combined in nested relationship with a second arm that is pivotally anchored to an expandable room. A track is mounted to the vehicle to allow support of the expandable room at a point distant from the anchor of the second arm. The track includes a downward turn near the vehicle side wall. In this manner, extension of the cylinder forces the arms apart and forces the expandable room to move along the track and down. To allow a flat floor configuration, the arms are combined, in cammed relationship so that as the floor of the expandable room moves through its range of motion, the arms continue to provide support and the cable remains under tension.
A further improvement, that may be employed with vertical arm extensions of the flat floor or the previously described traditional or xe2x80x9craised floorxe2x80x9d variety, is a moveable housing. If a vertical cam arm or hydraulic cylinder is visible from the vehicle interior, it is desirable to cover such elements to minimize the possibility of damage, contact, or contamination between the vehicle occupants and the mechanism. Such covers also serve to promote vehicle aesthetics. Therefore, there is disclosed a moveable cover for use in attachment with the moveable arms of the vertical cam mechanism to provide a cover for components that may otherwise protrude into the vehicle interior when the room is extended.